Measuring the parameters of a battery can be hindered due to loads that are applied to the battery. The parameters of an equivalent circuit can be measured while applying a pre-defined constant or variable load to the battery and analyzing the time domain or frequency domain response. However, during operation of a battery powered device, application of significant additional loads are undesirable due to possible distortion of operation. Additionally, a device for applying the additional load can be costly and/or complex. Moreover, the additional power usage may be unacceptable, especially in portable devices. Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.